Toxoplasmosis Skin Test

Norm of Toxoplasmosis Skin Test

Negative.
Positive
Current or past infection with Toxoplasma gondii.

 

Description of Toxoplasmosis Skin Test

Toxoplasmosis is a systemic, parasitic disease caused by the protozoon T. gondii. It is transmitted to humans by ingestion of the undercooked meat of infected animals or often by the ingestion of oocysts acquired from handling cat litter containing contaminated cat feces. It may also be transmitted to a fetus through the placenta of an infected mother. After ingestion, this parasite travels to various body tissues and is found grouped together in oocysts. Acquired toxoplasmosis often causes no symptoms in clients with intact immune systems. In immunosuppression, it may cause hyperpyrexia, lymphadenopathy, lymphocytosis, and, in some cases encephalitis, pneumonitis, myocarditis, myositis, and possibly death. Fetal congenital toxoplasmosis can cause severe birth defects, including blindness, hydrocephalus, and mental retardation, and may lead to fetal or postnatal death.

 

Professional Considerations of Toxoplasmosis Skin Test

Consent form NOT required.
Preparation

1. Assess whether a pregnant woman has handled cat feces during her pregnancy.
2. Assess whether the client has eaten any raw or undercooked meat.
3. Obtain an alcohol wipe, a 4-mL syringe, an intradermal needle, Toxoplasma antigen, and a control.

 

Procedure

1. Cleanse the forearm injection site with an alcohol wipe, and allow the area to dry.
2. Inject Toxoplasma antigen intradermally and record the site of injection. Inject the control in the other arm, and record the site of injection.
3. Read the skin test in 24–48 hours. A positive test is indicated by redness and induration >10 mm in diameter.

 

Postprocedure Care

1. See Toxoplasmosis serology—Serum for pregnancy precautions and precautions for persons with AIDS.

 

Client and Family Teaching

1. After the injection, return in 24–48 hours for a skin test reading.

 

Factors That Affect Results

1. None found.

 

Other Data

1. Many clients may be infected with T. gondii but are free of symptoms. Therefore any pregnant woman should be tested for the presence of antibodies to T. gondii. See Toxoplasmosis serology—Serum.